Renoprotective Effects of Dexmedetomidine Preconditioning in CABG Surgery

NCT07841054 | Completed

• 2 other identifiers: Bursa City Hospital Thesis 225-AKD-273
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Acute kidney injury (AKI) is one of the most frequent complications of coronary artery bypass graft (CABG) surgery performed with cardiopulmonary bypass (CPB). Even small postoperative rises in serum creatinine are associated with longer intensive care stay and higher mortality. Ischemia-reperfusion injury, the systemic inflammatory response elicited by contact of blood with the bypass circuit, and heightened perioperative sympathetic activity are believed to contribute to its development. Dexmedetomidine is a selective alpha-2 adrenergic receptor agonist used as a sedative and anesthetic adjunct. It attenuates sympathetic outflow and has shown anti-inflammatory and organ-protective properties in experimental models and in some cardiac surgical populations, but whether it reduces AKI after on-pump CABG surgery has not been established. This is a prospective, randomized, double-blind, placebo-controlled, single-center trial in adults undergoing elective CABG surgery with CPB. One hundred patients aged 18-80 years, ASA physical status II or III, with a preoperative serum creatinine below 1.5 mg/dL are allocated 1:1 to a dexmedetomidine group (n=50) or a control group (n=50). Patients in the dexmedetomidine group receive a loading dose of 1 microgram/kg over 15 minutes after central venous catheterization, followed by a maintenance infusion of 0.5 microgram/kg/h until the start of CPB. Patients in the control group receive an equal volume of 0.9% sodium chloride over the same period and with the same infusion scheme. In both groups the infusion is stopped when CPB begins; no study drug is given during bypass or postoperatively. Anesthesia, surgery, CPB conduct, fluid and vasoactive therapy, and postoperative intensive care follow a standardized protocol with identical numerical thresholds in both groups, applied by clinicians unaware of group allocation. The primary outcome is the incidence of postoperative AKI within the first 72 hours, staged according to the serum creatinine criteria of the KDIGO 2012 classification. Secondary outcomes are systemic inflammatory markers (white blood cell count, neutrophils, lymphocytes, neutrophil-to-lymphocyte ratio, C-reactive protein, procalcitonin), vasoactive drug requirement quantified by the vasoactive-inotropic score, need for renal replacement therapy, time to extubation, intensive care unit and hospital length of stay, and 30-day and 90-day mortality. All patients are followed until postoperative day 90. All variables assessed in the study are parameters obtained as part of routine clinical care in this patient population; no additional intervention or additional laboratory test is performed for study purposes.

Conditions

Dexmedetomidine; Postoperative Acute Kidney Injury; Cardiopulmonary Bypass Graft; Postoperative Complications

Keywords

Cardiac surgery-associated acute kidney injury; Dexmedetomidine; Coronary artery bypass grafting; Cardiopulmonary bypass; Renal protection; Vasoactive-inotropic score

Outcome Measures

Primary Outcomes (1)

• Incidence of postoperative acute kidney injury (KDIGO serum creatinine criterion)

  Number and percentage of participants developing acute kidney injury (AKI) of any stage (stage 1 or higher) according to the serum creatinine criterion of the KDIGO 2012 classification. The preoperative serum creatinine value is taken as the baseline; serum creatinine is measured at postoperative hours 0, 24, 48 and 72. AKI is defined as an increase in serum creatinine of 0.3 mg/dL or more from baseline within 48 hours, or a rise to 1.5 times baseline or higher, or the need for renal replacement therapy. The urine output criterion of the KDIGO classification is not applied.

  From the preoperative baseline measurement to postoperative hour 72

Secondary Outcomes (5)

• Vasoactive-inotropic score

  After separation from cardiopulmonary bypass, at intensive care unit admission (postoperative hour 0) and at postoperative hour 24

• Systemic immune-inflammatory response

  Preoperative baseline, at intensive care unit admission (postoperative hour 0) and at postoperative hour 24

• Time to extubation

  From ICU admission to extubation, assessed up to postoperative day 7

• Length of intensive care unit stay

  From ICU admission to ICU discharge, assessed up to postoperative day 30

• Length of hospital stay

  From surgery to hospital discharge, assessed up to postoperative day 30

Other Outcomes (2)

• All-cause mortality at 30 days

  Postoperative day 30

• All-cause mortality at 90 days

  Postoperative day 90

Study Arms (2)

Dexmedetomidine

EXPERIMENTAL

Patients undergoing elective coronary artery bypass graft surgery with cardiopulmonary bypass (CPB) who receive intravenous dexmedetomidine in the pre-bypass period. After central venous catheterization and a subsequent 5-minute period of hemodynamic stabilization, a loading dose of 1 microgram/kg is infused over 15 minutes, followed by a maintenance infusion of 0.5 microgram/kg/h until the start of CPB. The infusion is terminated with the initiation of CPB; no study drug is given during bypass or postoperatively. All other aspects of anesthesia, surgery, CPB conduct, fluid and vasoactive therapy, and postoperative intensive care follow a standardized protocol identical to that used in the control arm.

Drug: Dexmedetomidine

Control Group

PLACEBO COMPARATOR

Patients undergoing elective coronary artery bypass graft surgery with cardiopulmonary bypass (CPB) who receive an equal volume of 0.9% sodium chloride instead of dexmedetomidine. The placebo infusion is started after central venous catheterization and the subsequent 5-minute period of hemodynamic stabilization and is given over the same time intervals and with the same infusion scheme as in the dexmedetomidine arm (15-minute loading infusion followed by a maintenance infusion), and is terminated with the initiation of CPB. All other aspects of anesthesia, surgery, CPB conduct, fluid and vasoactive therapy, and postoperative intensive care follow the same standardized protocol as in the dexmedetomidine arm.

Drug: 0.9 % sodium chloride

Interventions

Dexmedetomidine DRUG

Intravenous dexmedetomidine, started after central venous catheterization and a 5-minute period of hemodynamic stabilization: loading dose 1 microgram/kg over 15 minutes, followed by a maintenance infusion of 0.5 microgram/kg/h until the start of cardiopulmonary bypass. The infusion is prepared by a physician who is not involved in intraoperative or postoperative care, in a syringe indistinguishable from the placebo syringe.

Dexmedetomidine

0.9 % sodium chloride DRUG

Intravenous 0.9% sodium chloride in a volume equal to that of the study drug, administered over the same time intervals and with the same infusion scheme as dexmedetomidine (15-minute loading infusion followed by a maintenance infusion until the start of cardiopulmonary bypass).

Control Group

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 to 80 years
• Scheduled for elective coronary artery bypass graft surgery with cardiopulmonary bypass at the study center
• American Society of Anesthesiologists (ASA) physical status class II or III
• Preoperative serum creatinine below 1.5 mg/dL
• Written informed consent obtained at the preoperative visit

You may not qualify if:

• Left main coronary artery stenosis greater than 50%
• Severe valvular dysfunction
• Severe left ventricular hypertrophy or cardiomyopathy
• Arrhythmia causing significant hemodynamic compromise
• Left ventricular ejection fraction below 35%
• Acute coronary syndrome or cardiovascular surgery within the preceding month
• Estimated glomerular filtration rate below 15 mL/min/1.73 m2
• Nephropathy due to uncontrolled hypertension and/or diabetes mellitus
• Treatment of hypertension with a combination of an angiotensin-converting enzyme inhibitor, a diuretic and an alpha-2 adrenergic agonist
• Morbid obesity
• Hepatic dysfunction attributable to substance abuse or alcoholism
• Previous severe drug allergy during administration of dexmedetomidine

Sponsors & Collaborators

• Bursa City Hospital: lead

Study Sites (1)

Bursa City Hospital

Bursa, nilüfer, 16010, Turkey (Türkiye)

Location

Related Publications (1)

• 1. Kidney Disease: Improving Global Outcomes (KDIGO) Acute Kidney Injury Work Group. KDIGO Clinical Practice Guideline for Acute Kidney Injury. Kidney Int Suppl. 2012;2(1):1-138. 2. Nadim MK, Forni LG, Bihorac A, et al. Cardiac and vascular surgery-associated acute kidney injury: the 20th International Consensus Conference of the ADQI (Acute Disease Quality Initiative) Group. J Am Heart Assoc. 2018;7(11):e008834. 3. Walsh M, Devereaux PJ, Garg AX, et al. Relationship between intraoperative mean arterial pressure and clinical outcomes after noncardiac surgery: toward an empirical definition of hypotension. Anesthesiology. 2013;119(3):507-515. (PMID 23835589) 4. Li J, Wang R, Wan J, et al. Postoperative central venous pressure is associated with acute kidney injury in patients undergoing coronary artery bypass grafting. Front Cardiovasc Med. 2022;9:1016436. (PMID 36465466) 5. Gaies MG, Gurney JG, Yen AH, et al. Vasoactive-inotropic score as a predictor of morbidity and mortality in infants after cardiopulmonary bypass. Pediatr Crit Care Med. 2010;11(2):234-238. (PMID 19794327) 6. Cho JS, Shim JK, Soh S, Kim MK, Kwak YL. Perioperative dexmedetomidine reduces the incidence and severity of acute kidney injury following valvular heart surgery. Kidney Int. 2016;89(3):693-700. (PMID 26444030)

  BACKGROUND

MeSH Terms

Conditions

Postoperative Complications

Interventions

Dexmedetomidine; Sodium Chloride

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Chlorides; Hydrochloric Acid; Chlorine Compounds; Inorganic Chemicals; Sodium Compounds

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate ,professor

Study Record Dates

• First Submitted: September 18, 2026
• First Posted: September 25, 2026
• Study Start: December 20, 2025
• Primary Completion: May 31, 2026
• Study Completion: August 1, 2026
• Last Updated: September 25, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)